Re: [RFC PATCH 00/35] overlayfs: stack file operations

[Miklos Szeredi]

On Wed, Apr 25, 2018 at 4:49 PM, J. R. Okajima <hooanon05g@xxxxxxxxx> wrote:
> Miklos Szeredi:
>> This patch series reverts the VFS hacks (with the exception of d_path) and
>
> I totally agree with removing d_real things.
> It must be good to the world.
>
> If I understand correctly, this series affects file_inode() too.
> So there may exist more commits to revert such as
>         fea6d2a6 2017-02-14 vfs: Use upper filesystem inode in bprm_fill_uid()


Yep.

>
> Here is another question.
> Does overlayfs support atomic_open?

No.  Overlayfs doesn't support network filesystems as modifiable
(upper) layer, and that's where atomic_open makes sense.  I think
actually no filesystem that defines atomic_open() can be used as upper
layer.   So that's currently not a worry.  If it turns out to be a
requirement to use such filesystem as upper, then I'll worry about
atomic_open().

Thanks,
Miklos